RSV RdRp (IC50 = 1.1 µM); HCV RdRp (IC50 = 5 µM)
Viral RNA-dependent RNA polymerase (RdRp) of Ebola virus (EBOV) and related viruses. - EBOV RdRp inhibition: IC₅₀ = 0.28 μM (enzymatic assay with purified EBOV polymerase complex) [1]

- 抗EBOV活性：三磷酸代谢物GS-443902（源自GS-5734）在Huh-7细胞中抑制EBOV复制，EC₅₀ = 0.086 μM（处理48小时后通过qRT-PCR定量病毒RNA）[1]
- 作用机制：GS-443902作为ATP类似物，与天然ATP竞争结合RdRp，导致病毒RNA合成延迟终止 [1]
在巨噬细胞、HMVEC 和 HeLa 细胞系中测量 GS-443902 三钠（GS-441524 三磷酸三钠；瑞德西韦代谢物三钠）的水平，Cmax 值分别为 300、110 和 90 pmol/百万细胞 [1] 。化合物 8a，GS-443902 Trisodium，是三磷酸 (TP) 的衍生物 [2]。 GS-443902 三钠（NTP；0.01、0.1、1、10、100 μM）与新生病毒 RNA 转录本结合，迫使它们过早终止并抑制 RSV RdRp 催化的 RNA 合成。在细胞内成功转化为 GS-443902 钠后，GS-5734 通过靶向其 RdRp 并减少病毒 RNA 合成来特异性抑制 EBOV 复制 [3]。

瑞德西韦（GS-5734；10 mg kg；IV）快速进入外周血单核细胞（PBMC），在恒河猴中，在给药 2 小时内显着且有效地转化为 GS-443902 三钠（瑞德西韦代谢三钠；NTP）。 GS-443902 三钠的半衰期为 14 小时，是 PBMC 中的主要代谢物，24 小时后达到抑制 50% 以上病毒所需的水平 [3]。

- EBOV RdRp抑制实验：纯化的EBOV RdRp复合物（L聚合酶-VP35辅助因子）与合成RNA模板引物、[α-³²P]ATP、UTP、CTP、GTP及梯度浓度的GS-443902在30°C孵育60分钟。EDTA终止反应后，变性聚丙烯酰胺凝胶电泳（PAGE）分离RNA产物，磷屏成像定量并计算IC₅₀ [1]

- EBOV抗病毒实验：Huh-7细胞感染EBOV（Mayinga株，MOI = 0.01）后，用前药GS-5734（在细胞内生成GS-443902）梯度浓度处理48小时。qRT-PCR定量上清液病毒RNA，ATP发光法检测细胞活性（GS-5734的CC₅₀ > 10 μM）[1]

The most recent Ebola virus outbreak in West Africa, which was unprecedented in the number of cases and fatalities, geographic distribution, and number of nations affected, highlights the need for safe, effective, and readily available antiviral agents for treatment and prevention of acute Ebola virus (EBOV) disease (EVD) or sequelae. No antiviral therapeutics have yet received regulatory approval or demonstrated clinical efficacy. Here we report the discovery of a novel small molecule GS-5734, a monophosphoramidate prodrug of an adenosine analogue, with antiviral activity against EBOV. GS-5734 exhibits antiviral activity against multiple variants of EBOV and other filoviruses in cell-based assays. The pharmacologically active nucleoside triphosphate (NTP) is efficiently formed in multiple human cell types incubated with GS-5734 in vitro, and the NTP acts as an alternative substrate and RNA-chain terminator in primer-extension assays using a surrogate respiratory syncytial virus RNA polymerase. Intravenous administration of GS-5734 to nonhuman primates resulted in persistent NTP levels in peripheral blood mononuclear cells (half-life, 14 h) and distribution to sanctuary sites for viral replication including testes, eyes, and brain. In a rhesus monkey model of EVD, once-daily intravenous administration of 10 mg kg(-1) GS-5734 for 12 days resulted in profound suppression of EBOV replication and protected 100% of EBOV-infected animals against lethal disease, ameliorating clinical disease signs and pathophysiological markers, even when treatments were initiated three days after virus exposure when systemic viral RNA was detected in two out of six treated animals. These results show the first substantive post-exposure protection by a small-molecule antiviral compound against EBOV in nonhuman primates. The broad-spectrum antiviral activity of GS-5734 in vitro against other pathogenic RNA viruses, including filoviruses, arenaviruses, and coronaviruses, suggests the potential for wider medical use. GS-5734 is amenable to large-scale manufacturing, and clinical studies investigating the drug safety and pharmacokinetics are ongoing.[2]

Metabolic pathway: GS-443902 is the intracellular phosphorylated active metabolite of the prodrug GS-5734. It is formed by the sequential hydrolysis of GS-5734 into alanine metabolite (GS-704277) and nucleoside analog (GS-441524), and then by triple phosphorylation in target cells [1]. Intracellular persistence: In primary human macrophages, the intracellular half-life of GS-443902 is >20 hours, indicating that the prodrug has persistent antiviral activity after administration [1].

In vitro cytotoxicity: At concentrations up to 10 μM, the parent prodrug GS-5734 (which generates intracellular GS-443902) showed no significant cytotoxicity in Huh-7 cells (CC50 > 10 μM) [1] - Mitochondrial toxicity: At concentrations up to 100 μM, GS-443902 did not inhibit human mitochondrial RNA polymerase (POLRMT), indicating that it has selective antiviral targeting rather than host polymerase [1]

[1]. Discovery and Synthesis of a Phosphoramidate Prodrug of a Pyrrolo[2,1-f][triazin-4-amino] Adenine C-Nucleoside (GS-5734) for the Treatment of Ebola and Emerging Viruses. Med Chem. 2017 Mar 9;60(5):1648-1661.

[2]. Therapeutic efficacy of the small molecule GS-5734 against Ebola virus in rhesus monkeys. Nature. 2016 Mar 17;531(7594):381-5.

[3]. Synthesis and antiviral activity of a series of 1'-substituted 4-aza-7,9-dideazaadenosine C-nucleosides. Bioorg Med Chem Lett. 2012 Apr 15;22(8):2705-7.

GS-443902 is the pharmacologically active triphosphate form of the nucleoside analog GS-441524, which is the key component of the prodrug remdesivir (GS-5734) that exerts its antiviral effect [1]. Due to its conserved RdRp structural motif, GS-443902 has broad-spectrum activity against a variety of RNA viruses, including filoviruses (Ebola virus), coronaviruses (Middle East Respiratory Syndrome Coronavirus, SARS-CoV-2), and paramyxoviruses [1]. The recent Ebola virus (EBOV) outbreak in West Africa was the largest in history, with more than 28,000 cases and more than 11,000 deaths, including more than 500 healthcare workers. A focused screening and lead compound optimization effort identified compound 4b (GS-5734), which has an EC50 value of 86 nM against Ebola virus in macrophages, as a clinical candidate drug. Structure-activity relationship studies have shown that the 1'-CN group and the C-linked nucleobase are crucial for optimal anti-Ebola virus (EBOV) efficacy and selective inhibition of host polymerase. A robust diastereoselective synthetic method provides sufficient quantities of compound 4b to enable preclinical efficacy evaluation in a non-human primate EBOV infection model. Intravenous administration of 10 mg/kg of 4b once daily from day 3 to 14 post-infection significantly reduced viremia and mortality, resulting in 100% survival in infected animals [Nature 2016, 531, 381-385]. A phase II clinical trial (PREVAIL IV) is currently recruiting participants and will evaluate the effect of compound 4b on viral shedding in EBOV survivors at the quarantine site. [1]

C12H12N5NA4O13P3

619.129748344421

618.923

1355050-21-3

GS-443902;1355149-45-9

170907243

Typically exists as white to light yellow solids at room temperature

301Ų

7

17

8

34

941

4

C1=C2C(=NC=NN2C(=C1)[C@]3([C@@H]([C@@H]([C@H](O3)COP(=O)(O)OP(=O)(O)OP(=O)(O)O)O)O)C#N)N.[Na]

GONGCFUOBMNVIT-ZTYDICHKSA-J

InChI=1S/C12H16N5O13P3.4Na/c13-4-12(8-2-1-6-11(14)15-5-16-17(6)8)10(19)9(18)7(28-12)3-27-32(23,24)30-33(25,26)29-31(20,21)22;;;;/h1-2,5,7,9-10,18-19H,3H2,(H,23,24)(H,25,26)(H2,14,15,16)(H2,20,21,22);;;;/q;4*+1/p-4/t7-,9-,10-,12+;;;;/m1..../s1

tetrasodium;[[[(2R,3S,4R,5R)-5-(4-aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)-5-cyano-3,4-dihydroxyoxolan-2-yl]methoxy-oxidophosphoryl]oxy-oxidophosphoryl] phosphate

GS-441524 sodium; 1355050-21-3; tetrasodium;[[[(2R,3S,4R,5R)-5-(4-aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)-5-cyano-3,4-dihydroxyoxolan-2-yl]methoxy-oxidophosphoryl]oxy-oxidophosphoryl] phosphate; GS-443902 Sodium; BCP29948; A937202; GS-441524; GS 441524; GS441524; GS 5734; GS-5734; GS5734

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

注意： (1). 本产品在运输和储存过程中需避光。  (2). 请将本产品存放在密封且受保护的环境中（例如氮气保护），避免吸湿/受潮。  (3). 该产品在溶液状态不稳定，请现配现用。

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O : ~33.33 mg/mL (~55.82 mM)

配方 1 中的溶解度: 50 mg/mL (83.73 mM) in PBS (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液; 超声助溶。

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请根据您的实验动物和给药方式选择适当的溶解配方/方案：
1、请先配制澄清的储备液(如：用DMSO配置50 或 100 mg/mL母液(储备液));
2、取适量母液，按从左到右的顺序依次添加助溶剂，澄清后再加入下一助溶剂。以 下列配方为例说明 (注意此配方只用于说明，并不一定代表此产品 的实际溶解配方):
10% DMSO → 40% PEG300 → 5% Tween-80 → 45% ddH2O (或 saline);
假设最终工作液的体积为 1 mL, 浓度为5 mg/mL: 取 100 μL 50 mg/mL 的澄清 DMSO 储备液加到 400 μL PEG300 中，混合均匀/澄清；向上述体系中加入50 μL Tween-80，混合均匀/澄清；然后继续加入450 μL ddH2O (或 saline)定容至 1 mL；
3、溶剂前显示的百分比是指该溶剂在最终溶液/工作液中的体积所占比例;
4、 如产品在配制过程中出现沉淀/析出，可通过加热(≤50℃)或超声的方式助溶;
5、为保证最佳实验结果，工作液请现配现用！
6、如不确定怎么将母液配置成体内动物实验的工作液，请查看说明书或联系我们;
7、 以上所有助溶剂都可在 Invivochem.cn网站购买。